The invention relates to improvements in transfer of a continuous web substrate between printing, feed, storage, finishing/cutting and/or other devices, especially high speed xerographic printing devices, to include simplex printing systems including or requiring separate, dual, or multiple print engines.
In particular, in the embodiments herein the page images for the opposing sides of the web may be transferred efficiently thereto from single conventional photoreceptor or other imaging surface of a single print engine with two separate but closely spaced and alternatingly engaged image transfer stations, and a special web inversion and variable length web loop control system, in plural page image batches, from a common transfer area.
Several known patents relate to the field of the present invention, and each of the following are hereby incorporated herein in their entirety:
Boeck et al., U.S. Pat. No. 5,467,179 teaches a turnover device for turning a web-shaped recording medium over between two electrophotographic printer or copier devices working in tandem mode, the crossing point of the turning elements is arranged offset a distance of xcfx80/2 in the direction of the deflector element relative to the middle of the supplied recording medium, taking the cross sectional dimensions of the turning elements into consideration. The lateral offset of the recording medium is thereby avoided. In other words, the web inverting device of Boeck inverts a web and the web exits in the same paper path direction as its entrance path. This fixed path is useful for in-line tandem simplex printers.
Knapp, U.S. Pat. No. 3,548,783 teaches a sheet transport apparatus for both cut sheet and web-type flexible material for changing the path of the material by driving it through guide means curved to change the direction of movement of the flexible material moved therethrough by rollers. By strategically preshaping curved units, paths of feed may be manipulated for inverting the material as the path is changed. A hollow guide track or strategically placed guides and drive rollers are taught by Knapp for use to change the path of the input. In other words, the web inversion apparatus of Knapp requires entrance and exit angles to be fixed and, more particularly, to be fixed at 90 degrees.
It is desired to create a web inversion apparatus that both inverts a web substrate and allows wide flexibility between entrance and exit angles. Such a flexible web inversion apparatus may then be coupled with a wide assortment of printing, copying, finishing, and web supply and receiving devices in a manner that enables a web supplying device to work in tandem with a first web receiving device and then, subsequently, to work in tandem with a second web receiving device without the need to substantially move any of the devices other than change in orientation of the web inversion apparatus.
The disclosed embodiments of the present invention may desirably employ known existing simplex or duplex web printers and peripheral devices/systems. Duplex web printing may performed by inverting a web for printing between serial printers according to a transfer apparatus and/or systems of the present invention which can be moved and or pivoted to any desired location or angle of web entry or exit. The web transfer system described and illustrated herein inverts and transfers the continuous web to and/or from printing and other devices in a variety of variable and flexible scenarios. For example, faster and more reliable handling of the physical image bearing substrate is made possible for xerographic and other copiers, offset and digital printers, and multifunction machines.
In one embodiment of the present invention, a system for inverting a continuous web substrate having a defined direction of movement comprises (a) a continuous web print substrate supply system providing controlled feeding of said continuous web print substrate to a single web print substrate receiving system, and (b) a web transfer apparatus for inverting said continuous web, said transfer apparatus including a hinge point whereby an angle of entry of the web substrate to the web transfer apparatus can be varied relative to an angle of exit of the web substrate web from said web transfer apparatus.
In another embodiment of the present invention, an apparatus for inverting a web substrate having a width dimension, comprises: (a) a hinge assembly having a hinge axis and a first attachment section and a second attachment section placed along said axis; (b) an entrance turning surface, coupled to the hinge assembly within the first hinge attachment section and having an axis extending away from the hinge assembly, said entrance turning surface having an end section away from the hinge assembly; (c) a second turning surface, coupled to the hinge assembly within the second hinge attachment section at a location spaced apart from the first hinge attachment section, said second turning surface being arranged in a plane substantially parallel to the plane containing the axis of the entrance turning surface and that is substantially parallel to the axis of the hinge assembly, said second turning surface having an axis extending away from the hinge assembly and angled toward the end section of the entrance turning surface; (d) an exit turning surface, coupled to the hinge assembly within the second hinge attachment section at an angle adjustable with respect to the angle at which the entrance turning surface is coupled to the hinge assembly, said exit turning surface having an axis extending away from the hinge assembly in a different plane than the plane containing the axis of the entrance turning surface and having an end section away from the hinge assembly; and (e) a third turning surface, coupled to the hinge assembly within the first hinge attachment section at a location spaced apart from the second hinge attachment section, said third turning surface being arranged in a plane substantially parallel to the plane containing the axis of the exit turning member and that is substantially parallel to the axis of the hinge assembly, said third turning surface having an axis extending away from the hinge assembly and angled toward the end section of the exit turning surface; whereby a web paper path is formed within the inverting apparatus by feeding the web over the entrance turning surface, then around the second turning surface toward and around the third turning surface toward the exit turning surface where it is turned before exiting the inverting apparatus.
In another embodiment of the present invention, a web inverting apparatus comprises (a) a hinge assembly and (b) an entrance module and an exit module, each such module coupled to said hinge assembly such that the hinge assembly provides variability in the angle between the entrance module and the exit module so that a web supply system may feed a web substrate into the entrance module and the web exits the exit module in an orientation substantially inverted to its entrance orientation and so that the web substrate may enter the entrance module at one angle in respect to a web substrate supply system and exit at a different angle.
In yet another embodiment of the present invention, a method for inverting a web substrate in a web inverting device comprises: (a) feeding the web substrate around an entrance turning surface toward a second turning surface, said entrance turning surface being coupled to a hinge assembly within a first attachment section of said hinge assembly and said entrance turning surface having an end section away from the hinge assembly; (b) weaving the web substrate path around the second turning surface toward a third turning surface, said second turning surface being coupled to the hinge assembly within a second hinge attachment section at a location spaced apart from the first hinge attachment section, said second turning surface being arranged in a plane substantially parallel to the plane containing the axis of the entrance turning surface and that is substantially parallel to the axis of the hinge assembly, said second turning surface having an axis extending away from the hinge assembly and angled toward the end section of the entrance turning surface; (c) turning the web substrate path around the third turning surface toward an exit turning surface, said third turning surface being coupled to the hinge assembly within the first hinge attachment section at a location spaced apart from the second hinge attachment section, said third turning surface being arranged in a plane substantially parallel to the plane containing the axis of the exit turning member and that is substantially parallel to the axis of the hinge assembly, said third turning surface having an axis extending away from the hinge assembly and angled toward the end section of the exit turning surface; and (d) exiting the web substrate from the web inverting device by turning the web substrate around the exit turning surface toward a preferred exit orientation, said exit turning surface being coupled to the hinge assembly within the second hinge attachment section at an angle adjustable with respect to the angle at which the entrance turning surface is coupled to the hinge assembly, said exit turning surface having an axis extending away from the hinge assembly in a different plane than the plane containing the axis of the entrance turning surface and having an end section away from the hinge assembly.
In the description herein the term xe2x80x9cwebxe2x80x9d refers to an elongated flexible material of paper, plastic, or other suitable physical substrate for printing images thereon. As to specific components of the subject apparatus, or alternatives therefor, it will be appreciated that, as is normally the case, some similar components are known per se in other apparatus or applications which may be additionally or alternatively used herein, including those from art cited herein. All references cited in this specification, and their references, are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features, and/or technical background. What is well known to those skilled in the art need not be described here.